Emergency gate opening apparatus

Abstract

A gate opening device for shifting a gate from a closed position to an open position on loss of power to a motive device includes a housing, the motive device carried by the housing, and a drive shaft coupled to and rotatable by the motive device. A drive member is coupled to the drive shaft and capable of being connected to a gate for causing shifting movement thereof. A base plate is coupled to the drive shaft and a drive plate is coupled to the drive member and pivotally coupled to the base plate. A shear pin engages the drive plate and the base plate, preventing relative pivoting thereof. The shear pin is formed of a material which allows a shearing effect on a specified torque or force, causing the shear pin to break or shear and allow relative pivotal movement of the drive plate and the base plate.

Having thus described my invention, what I desire to claim and secure by Letters Patent is:  
     
       1. An apparatus for shifting a gate from a closed position to an open position on loss of a driving means comprising: 
       (a) a housing,  
       (b) said driving means associated with said housing,  
       (c) a drive member operatively connected to said driving means and capable of being connected to a gate for causing shifting movement of same,  
       (d) a locking mechanism operatively associated with said drive member,  
       (e) a manually operable release member operatively connected to said locking mechanism,  
       (f) a drive shaft operatively connected to said driving means and being rotatable by said driving means, said drive member being operatively connected to said drive shaft and rotatable thereby, said drive member being disconnected from said drive shaft upon actuation of said release member,  
       (g) said release member being located on a drive plate engagingly connected to a base plate, and  
       (h) said release member comprises a shear pin of a material which allows a shearing effect on a specified torque or force, said shear pin adapted to break or shear to disengaging the drive member from said driving means when said shear pin is sheared.  
     
     
       2. The apparatus of  claim 1  further characterized in that the drive plate and base plate are connected by a mounting bolt opposite the shear pin. 
     
     
       3. The apparatus of  claim 2 , further characterized in that the drive plate will rotate on the mounting bolt allowing the drive plate to disengage from the base plate for permitting shifting movement of the gate. 
     
     
       4. The apparatus of  claim 3  wherein the drive plate is engaged and connected to a said drive member. 
     
     
       5. The apparatus of  claim 4  wherein the base plate becomes operatively disengaged from said drive shaft upon actuation of said release member. 
     
     
       6. The apparatus of  claim 5  further characterized in that said gate is adapted to be rotated hingeably from a closed position rotating on the axis of the mounting bolt fitted to the drive plate and base plate. 
     
     
       7. An apparatus for shifting a gate from a closed position to an open position on loss of a driving means comprising: 
       a housing;  
       said driving means carried by said housing,  
       a drive shaft coupled to and rotatable by said driving means;  
       a drive member coupled to said drive shaft and capable of being connected a gate for causing shifting movement of same;  
       a base plate coupled to the drive shaft;  
       a drive plate coupled to the drive member and pivotally coupled to the base plate; and  
       a shear pin engaging the drive plate and the base plate, preventing relative pivoting thereof, the shear pin being of a material which allows a shearing effect on a specified torque or force, said shear pin adapted to break or shear allowing relative pivotal movement of the drive plate and the base plate.